Which reference frame and epoch does adjust.exe report? A reporting discrepancy noted.

[jhaasdyk-au]

The purpose of this github discussion is to:

• record findings, feedback and questions to inform planned discussions with icsm-au/DynAdjust subject matter experts
  i.e. to inform additional user(self)-education, or potential enhancements or defects.

All findings and recommendations are my own and may not correctly represent current or planned DynAdjust behaviour.

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From where does adjust.exe gather the reference frame (and epoch) used for reporting?
The ADJ file and the adjust.exe output can differ in the reported epoch.

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Consider the following examples skye_tutorial_test_datum.txt (rename as .bat batch file to run). Test# below matches this batch file.
(Note: The geoid has been chosen to match the source data reference frame. Choice of geoid does not affect this issue)

<--------------<Import.exe&geoid.exe>, <ADJfile output ---->, <adjust.exe cmd output>
Test#, Source, RefFrame, Geoid------>, RefFrame & Epoch---->, RefFrame & Epoch------>,
Test1, GDA94-, GDA94---, AUSGeoid09--, GDA94----, 01.01.1994, GDA94----, 01.01.1994,
Test4, GDA94-, GDA2020-, AUSGeoid09--, GDA2020--, 01.01.1994, GDA2020--, 01.01.2020
Note in particular that the ADJ file and the adjust.exe output differ in the reported epoch for Test 4.

• The adj file reports the epoch from the input dataset (?? the header from that file?? the measurements ??)
• The adjust.exe output reports the default epoch of the default reference frame (??)

Further, if reftran is used to set the reference frame and a new epoch, (per Setion 4.7.2) then this reporting discrepancy disappears.
<--------------<Import.exe&geoid.exe>, <reftran.exe options>, <ADJfile output ---->, <adjust.exe cmd output>
Test#, Source, RefFrame, Geoid------>, RefFrame & Epoch---->, RefFrame & Epoch---->, RefFrame & Epoch------>,
Test7, GDA94-, GDA94---, AUSGeoid09--, GDA94----, 12.06.2035, GDA94----, 12.06.2035, GDA94----, 12.06.2035
Test8, GDA94-, GDA2020-, AUSGeoid09--, GDA94----, 12.06.2035, GDA94----, 12.06.2035, GDA94----, 12.06.2035
Test9, GDA94-, GDA2020-, AUSGeoid09--, GDA2020--, 12.06.2035, GDA2020--, 12.06.2035, GDA2020--, 12.06.2035

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For discussion with icsm-au/DynAdjust SME)

1. Discrepancy in epoch output for (adjfile and adjust.exe report different epochs).
2. Discuss the validity of using reftran to set the epoch of a static datum (e.g. reftran skye_set_GDA2020_AG09_reftran_GDA2020_epoch -r GDA2020 -e 12.06.2035)
   This is really a case of mixing and matching what ‘epoch’ is used for. See related discussion Observation epoch vs reference frame epoch: Explicitly distinguish? · Discussion #195 · icsm-au/DynAdjust (github.com)

[Post truncated 12/09 to remove extraneous discussion on Reference Frame documentation]

[rogerfraser]

Thanks @jhaasdyk-au for capturing the results of your experiences.

The inconsistency you're seeing between the adj file and screen output when running Test4 isn't good and should be fixed. Expect to see a fix in the next release.

[jhaasdyk-au]

Thanks Roger for reaching out by email (nominally from related Issue #215)

On further consideration, I've also suggested to you the possibility of requiring more user intervention in order to permit a datum change or to mix and match datums. Currently datum change is implicit in adoption of the default adjustment datum with 'only' a warning.

This note is just to note that email conversation of ~16/05/2023, which may or may not spawn separate issues.